Display device

ABSTRACT

A display device that is incorporated into a building structure includes at least one rigid block composed of a robust grindable composition. The block has at least one light emitting device molded therein, the light emitting device being electrically connected to a power source to enable illumination of the light emitting device when in use. The light emitting device is visible from at least one surface of the block for providing at least one illuminated display surface in use. The block is incorporated within the building structure such that the display surface is exposed at and protrudes from at least one surface of the building structure. At least one surface of the block is ground to render visible the light emitting device for providing the display surface and to render the surface substantially non-slippery so as to prevent an object in contact with the display surface from slipping thereon in use. A method of making the display device is further disclosed.

BACKGROUND AND SUMMARY OF THE INVENTION

The present invention relates to a display and, in particular, to adisplay device which may be incorporated in the floors or walls of abuilding structure.

Conventional illuminated display devices such as strip tube with lightsare generally designed for mounting on a wall or like surface and may bearranged to display messages. One problem with such devices is that theycan be fragile and temperamental so that, unless mounted beyond normalreach, they are unsuitable for use in public areas. For example, anilluminated "FIRE EXIT" message of the conventional display device mustbe mounted in a position where an exiting crowd will not damage thedisplay.

Furthermore, conventional display devices as described above aredesigned for normal indoor use and are consequently not suitable foroutdoor, all-weather conditions, or for use under water. Generally,known outdoor type display devices are complicated, sealed structuresdesigned for specific environments.

An object of the present invention is to provide a simple and convenientdisplay device which overcomes the abovementioned disadvantages.

According to a first aspect of the invention there is provided a displaydevice comprising one or more illuminable devices embedded in a robustcomposition.

The robust composition may be an anti-slip composition as described inpatent application number 9213885.8. This patent application discloses acomposition for an anti-slip tread comprising an epoxy resin, a blockedpolyurethane and an inert aggregate. The illuminable devices may bepartially embedded so that the surfaces of the illuminable devices arevisible at or above the surface of the robust composition.Alternatively, the illuminable devices may be wholly embedded and thesurface of the robust composition may be ground until the illuminabledevice's surfaces are visible. Such grinding may include partialgrinding of the illuminable device surfaces.

The illuminable devices may be incandescent bulbs, light-emitting diodeshereinafter referred to as LEDs, liquid crystal displays, opticalfibres, laser diodes electroluminescent devices or the like and may bemounted on rigid or flexible printed circuit board (pcb), standardstrip-board or wire loom.

Preferably the display device is in the form of one or more independentpanels, each of which may be connected to a power supply via fly-leadsor a conductor line and/or connected to a similar independent panel. Theilluminable devices of each panel may be arranged to display aparticular pattern, letter, numeral or symbol, and when interconnected,a number of such panels may combine to display a complete picture ormessage.

Alternatively, the display device may be in the form of a continuousstrip. The illuminable devices may be mounted on a continuous strip ofrigid or flexible pcb. In some applications the display device may be inthe form of a single illuminable device embedded in a disc of robustcomposition.

Such a disc is particularly useful in for example precast concretesurfaces or terrazzo surfaces such as stairs or steps. The discs may beinlaid so that their surfaces are flush with the floor or wall surfaces.Alternatively, the discs may be partially or substantially raised abovethe surface to provide for example a non-slip or impact resistant tread.

Display devices of the invention in the form of continuous strips, withthe illuminable devices preferably not grinded off, find particularapplication in the field of low location lighting such as in commercialpremises and marine applications.

The display device of the invention may also be in the form of a smallblock which may fit within a suitably configured extrusion embedded orsecured to a floor surface, carpet, skirting or the like. A miniaturepcb having a single or multichip (for example four-orb) LED or otherilluminable device mounted thereon may be encapsulated or embedded inthe small block. Preferably a channel section extrusion having twogrooves is provided to receive such display devices along the lengththereof. The display devices may be connected in series in spaced apartrelationship to form a discrete strip along the grooves. Alternativelythe display devices may be connected adjacent each other and side byside in the grooves to form a display message or the like such as anEXIT sign located in the floor or carpet groove. A plastic or the liketransparent or semi-transparent cover may be provided for the extrusionand a clip for example of metal may be provided to releasably retain thecover on the extrusion.

Preferably, and particularly for fire hazard locations, the robustcomposition comprises a fire and/or flame retardant material and anycables linking the display devices are coated with a suitable plasticsuch as polytetrafluoroethylene.

The illuminable devices may be connected electrically in series, inparallel or in series and parallel and each such device may becontinuously or discretely illuminable, e.g. flashing LEDs. Thus, asingle display device or part of a display device may include someilluminable devices connected in parallel and some connected in series.The display device composition and the illuminable devices may have anysuitable color and preferably such coloring is chosen to provide highcontrast between the illuminated illuminable devices and the backgroundcomposition color. The robust composition may be wholly or partiallytransparent.

A layer of transparent material may be included between the illuminabledevices and the surface of the display device composition. Suchtransparent material may be glass and may be ground to provide ananti-slip surface.

The display device may have any suitable shape, and, as described above,preferably forms a panel such as a floor or wall tile or is in the formof a disc, strip or small block. The display device may be shaped toform a stair nosing and the illuminable devices may be arranged to bevisible from one or more surfaces of the robust composition.

According to a further aspect of the invention, there is provided amethod of producing a display device comprising the steps of arrangingone or more illuminable devices in a mold and forming a robustcomposition in the mold. Preferably such method includes the step ofmounting such illuminable devices on a printed circuit board or the likeprior arranging them in the mold.

Further steps may include arranging one or more transparent orsemi-transparent sheets in the mold adjacent the surfaces of theilluminable devices and/or grinding the surface of the formedcomposition to enhance the anti-slip properties thereof.

The display device of the present invention is particularly suitable foruse as an emergency exit guidance system. The low voltage supply makesthe device electrically safe so that it can be used outdoors and inhazardous industrial situations.

The method of producing the display device is such as to provide asealed unit which can safely be used under moist conditions such as onships or underwater. The display device may include a robust compositionwhich has enhanced fire-proof properties.

The display device can be fitted to floors, walls, curbs, skirtings,stairs, doors or the like by any suitable means including cementing,fixing by means of pre-drilled apertures and screws or adhesion.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described further by way of example only andwith reference to the accompanying drawings in which:

FIG. 1 illustrates one embodiment of the invention with connectedpanels;

FIG. 2 shows a second embodiment of the invention with connecting meansconnecting successive panels; and

FIG. 3 shows alternative embodiments of display device of the invention;

FIG. 4 shows a printed circuit board embedded within the robustcomposition; and

FIG. 5 shows the display device incorporated within a buildingstructure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1 a display device 2 is comprised of fourinterconnected panels 4, 6, 8, 10, each displaying an individual letterE, X, I, T respectively. The letters are formed by appropriatearrangement of LEDs 12. Each panel is independent so that any number ofpanels may be connected to give any suitable message. Fly-leads 14connect to a low voltage dc/ac power source.

FIG. 2 illustrates a connecting panel arrangement for use as a guidewaysystem. LEDs 12 are incorporated in longitudinal panels 16, 18 which areconnected by means of connector 20 so that the LEDs form a continuousguideway. The connector 20 has prongs 22 which mate with correspondingapertures 24 in the end walls of the panels 16, 18. Conductors 26 may behollow or solid. The prongs 22, apertures 24 and conductors 26 form acontinous bus line when the panels are connected. The dc/ac power sourcemay be located either locally or remotely at one end of the guidewaysystem.

FIG. 3 illustrates further embodiments of display device 32 havingsuitably shaped robust compositions 34 and embedded LEDs 36. As shown,the robust composition 34 is in the form of a circular or rectangularshaped block, each having a surface 38 which is ground so as to rendervisible the LED 36 and to render the surface substantially non-slipperyso as to prevent an object in contact with the display surface fromslipping thereon in use.

FIG. 4 illustrates a block similar to the ones shown in FIG. 3 wherein aprinted circuit board (PCB) 40 is embedded within the robust composition34. As shown, the LEDS 36 are mounted on the PCB 40 in such a mannerthat they extend upwardly through and out of the robust composition 34.

FIG. 5 illustrates a building structure generally indicated at 42 havinga display device 32 with its display surface 38 protruding through thebuilding structure. An extruded body 44 having a groove 46 formedtherein is shaped to receive the block (robust composition 34) of thedisplay device 32. Preferably, the body 44 together with the block 34 isincorporated within the building structure 42.

In manufacture, the LEDs are mounted either in series or in parallel ona PCB or the like and the whole circuit is embedded in the panel bymolding the panel around it. Some of the LEDs may be mounted in parallelwhile some may be mounted in series over the whole or part of the PCB orlike support structure. The surface of the panel is ground down so thatthe LEDs are displayed and the non-slip properties of the surface areenhanced.

It will be appreciated that the present invention is not intended to berestricted to the details of the above described embodiment which isdescribed by way of example only. In particular, any suitable hardwearing material may be used in the molding process and the illuminateddevices may be arranged in one or more panels or strips to form anyrequired message or pattern for display.

What is claimed is:
 1. A display device that is incorporated into abuilding structure, the display device comprising at least one rigidblock composed of a robust grindable composition, the block having atleast one light emitting device molded therein, the light emittingdevice being electrically connected to a power source to enableillumination of the light emitting device when in use, the lightemitting device being visible from at least one surface of the block forproviding at least one illuminated display surface in use, the blockbeing incorporated within the building structure such that the displaysurface is exposed at, and protrudes from at least one surface of thebuilding structure, at least one surface of the block being ground torender visible the light emitting device for providing said displaysurface and to render the surface substantially non-slippery so as toprevent an object in contact with the display surface from slippingthereon in use.
 2. A display device as set forth in claim 1, the robustcomposition being substantially non-flammable.
 3. A display device asset forth in claim 1, the light emitting device being mounted on aprinted circuit board.
 4. A display device as set forth in claim 3, theprinted circuit board being embedded in the block.
 5. A display deviceas set forth in claim 1, the block being in the form of a disc.
 6. Adisplay device as set forth in claim 1, the block being adapted to bereceived in an extruded body having a correspondingly shaped groovetherein, the body together with the block being incorporated within thebuilding structure.
 7. A method of producing a display device forincorporation into a building structure comprising the stepsof:arranging at least one light emitting device in a mold; molding agrindable robust composition around the light emitting device such thatthe light emitting device is embedded in the robust composition to forma block; and grinding at least one surface of the block to rendervisible the light emitting device for providing at least one displaysurface in use and to render the display surface substantiallynon-slippery so as to prevent an object in contact with the displaysurface from slipping thereon in use.
 8. A method as set forth in claim7, further comprising the step of mounting the light emitting device ona printed circuit board before arranging the light emitting device inthe mold.